Autophagy (Series O: Operations)

In this weekend's programme, Bill Bailey refers to a curious phenomenon he calls "autophagy" in bar-tailed godwits. He describes these birds on migration as deriving their energy for their flight by eating parts of their own liver (which presumably regenerates afterwards when their strenuous activity is over).

I was struck by the bizarreness of this assertion. Being a keen ex-birdwatcher myself, I do know what bar-tailed godwits are. I've seen quite a few of them myself. But I've never come across this "autophagy" business in these birds in all the field guides I've browsed or bird magazines I've read. You'd think something as bizarre as this would be worth a mention in some of the ornithological literature available – but, apparently, no.

So I did a search on the Internet. First, let us be clear on the terminology. The phenomenon described by Bill is perhaps better called "auto-cannibalism" or "self-cannibalism" – the term autophagy has a different technical meaning in microbiology, referring instead to the process of cells destroying themselves when they're past their sell-by date. I have only managed to find one Internet reference to self-cannibalism in bar-tailed godwits: in a reference to a book entitled Bill Bailey's Remarkable Guide to British Birds.

Obviously, that is getting nowhere. So, I'd like to know where exactly did Bill Bailey obtain his "remarkable" ornithological facts from.